Ink cartridge assembly for ball-point pens



April 1958 v. H. BARNEQ mww :mflw

INK CARTRIDGE ASSEMBLY FOR BALL- POINT PENS Filed June 4, 1954 INVENTORL hc'ron H. BARNEs BY ATTORNEYS United States Patent ice INK CARTRIDGE ASSEMBLY FOR BALL-POINT PENs Victor H. Barnes, Palo Alto, Calif., assignor to Micropoint, Incorporated, Sunnyvale, Calif., a corporation of California Application June 4, 1954, Serial No. 434,459

Claims. c1. lilo-42.4)

This invention relates to a new and improved ink cartridge assembly for ball-point pens.

At the present time, I am aware of 133 different commercial makes or brands of ball-point pens on the market today. All of these commercial pens of which I have knowledge incorporate a removable ink-containing cartridge which, fundamentally, consists of an elongate hollow tube containing ink, and provided at one end with a ball writing point in fluid communication with the said ink reservoir. Moreover, all of the pens with which I am familar are designed so that when the ink in the original cartridge is exhausted, a refill cartridge can be inserted within the pen casing in lieu of the original cartridge. Although there have been attempts in the past to provide a single cartridge refill assembly that can be employed with the large majority of different makes and models of commercial pens, none of these prior attempts has been successful in providing a satisfactory refill assembly capable of being utilized with all of the commercial makes of pens on the existing market. In this regard, among the large group of commercial pen brands, there exists variation in both the length and diameter of ink cartridges employed, and in the type of operating mechanisms incorporated in the pens for extending and retracting the ball-point ends of the cartridges relative to the pen bodies.

It is a principal object of the present invention, therefore, to provide a ball-point pen ink cartridge assembly that can be adapted and assembled so as to provide a satisfactory and eflicient refill unit for any oneof the l33comrnercial brands of pens on the market at the present time with which I am familiar.

The particular embodiment of the invention which is illustrated in the drawingsyand which will be described hereinafter in greater detail, is shown as comprising an elongate integral length of tubing open at its upper end and provided at its forward end with the usual ball writing point in fluid communication with an ink reservoir contained in the tube. The upper portion of the tube body is formed with a plurality of annular break-off grooves spaced at predetermined intervals from the ball-point end corresponding to the varying lengths of ink cartridges utilized by the difierent commercial makes of pens. Each of the annular grooves is cut to a depth equal to at least a major portion of the thickness of the tube body to provide, in efiect, a series of structurally weak break-off points located at preselected intervals lengthwise of the tube body. v

The present assembly also comprises first and second tubular sleeves, each having a diameter only slightly larger than the outside diameter of the cartridge body, and adapted to be slidably mounted on the tubular cartridge in:end-to-endrelationship. As will more fully appear hereinafter, the sleeves may be slidably positioned on the tubularcartridge body with adjoining ends of the sleeves disposed coincident with any one ,of the break-off grooves whereby said adjacenfsleeve ends provide leverage fulcrum points to facilitate breaking of the tube precisely 2,829,623 Patented Apr. 8 8

at the point of any preselected groove without danger of bending, breaking or otherwise deforming any other part of the cartridge tube body.

Another principal object, therefore, of the present invention is to provide an elongate ball-point pen cartridge consisting of a single and integral length of tubing formed with a plurality of annular break-off grooves spaced at predetermined intervals along the cartridge tube body, in conjunction with a pair of sleeves slidably positionable on the cartridge tube body in end-to-end relationship with adjacent ends of the sleeves substantially coincident with any one of the break-off grooves to provide fulcrum leverage points proximate the groove where the break-off is to be made.

An additional object and advantage of the tubular sleeves is to provide a means for efiectively'enlarging the outside diameter of the cartridge body in refill applications where the situation requires a larger diameter tube than defined by the body of the cartridge refill tube itself.

Other numerous objects and advantages of the invention will become apparent upon reading the following specification, and referring to the accompanying drawings in which similar characters of reference represent corresponding parts in each of the several views.

In the drawings:

Fig. 1 is a view in side elevation of an ink cartridge assembly embodying the invention and showing the component elements in exploded relation; r

Fig. 2 is an enlarged side elevational View of the car tridge tube, but showing the major portion of its length in section;

Fig. 3 is a side elevational view partly in section of the cartridge tube with the sleeves mounted slidably on the tube and illustrating how the sleeves may be employed as leverage means to break the tube at one of its break-off points; a

Fig. 4 is a longitudinal sectional view of a first type of ball-point pen construction with an ink cartridge embodying the present invention installed therein;

Fig. 5 is a longitudinal sectional view of a second type of pen construction with the present cartridge assembly installed therein; and

Fig. 6 is a fragmentary longitudinal sectional view of a third type of pen construction with the present cartridge assembly installed therein.

Referring now more particularly to the drawings, the ball-point cartridge assembly therein illustrated and embodying the invention is shown as comprising, generally, a cartridge tube A, a shorter sleeve B, a longer sleeve C, and a coil spring D.

The cartridge tube, heretofore indicated generally at A, is shown as comprising an elongate integral section of preferably /s inch brass tubing, which in the preferred commercial form may be made approximately 4% inches long, and provided at its forward or lower end with a ball type writing point unit indicated at 11. The ball-point unit 11 may be considered as conventional in construction and operation, such units being well-known and understood in the art. It will suffice to remark that the ball-point unit 11 is mounted on the forward end of the cartridge tube A in fluid communication with the reservoir of ink, indicated at 12, contained within the tube. In this regard, the tube may be filled with ink throughout the major portion of its length, and in the example given, the tube is shown as being filled with ink to a point approximately 2% inches from the writing point end thereof. In view of the fact that the ink commonly employed in ball-point pens is relatively viscous, its surface tension is sufficient to maintain it within the tube without the necessity of mechanically blocking the tube with a solid plug or the like to keep the ink from flowing out the open end thereof.

The integral. brass tube cartridge A is also formed with a plurality of spaced annular break-off grooves such as indicated at 16. More specifically, annular grooves 16 are formed at predetermined spaced intervals, and in the drawings, there is shown a total of grooves spaced at preselected distances from the writing point end of the cartridge. In this regard, I am aware of 133 commercial pens on the market at the present time, but because many of the different brands of pens employ the same size ink cartridge, I have found that 11 different cartridge tube lengths will fit all 133 commercial makes of pens. Accordingly, the overall length of the tube can be made to fit the commercial make or makes of pens requiring the longest cartridge refills, and the ten break-01f grooves 16 are spaced from the writing point end of the cartridge to correspond to the ten relatively shorter lengths of cartridge tubes required. It is also desirable to locate the innermost break-off groove, indicated at 16 in spaced relation from the terminal point of the ink reservoir 12, so that in instances where the cartridge tube is broken off at point 16 there will not occur a breaking through of the ink reservoir itself with consequent leakage or spillage of ink from the tube.

' In the preferred arrangement, the inch brass tube from which the cartridge tube A is formed may have a wall thickness of approximately .012 inch and each of the circumferential break-off grooves 16 may be cut or otherwise formed to a depth of .007 to .010 inch deep and from .005 to .012 inch wide. Although considerable variation in the wall thickness of the tube and in the depth and width of any of the annular break-off I grooves may be practiced within the spirit and teachings of the present invention, the above specific tolerances have been found to provide a cartridge tube capable of fulfilling the principal advantages and objects of the invcntion above enumerated.

The slidable sleeves heretofore indicated generally at B and C, respectively, may each be formed of integral sections of tubing made of brass or other material. Said sleeves are both preferably formed with an inside diameter only slightly greater than the outside diameter of cartridge tube A, whereby the sleeves can he slidably mounted on the cartridge tube in end-to-end relation in the manner and for the reasons to be explained hereinafter. should, however, be less than the transverse distance between the laterally projecting cars 14 or" the cartridge tube whereby the said cars will function as stop or abutment members to prevent slidable movement of the sleeves beyond the point of crimp 3.3 in certain applications of use to which the sleeves are intended to be put and which will also be explained hereinafter.

Although sleeves and C are provided as a part of the present cartridge assembly to fulfill several functions, one of the major and most important functions of the sleeves is illustrated in Fig. 3. As hereinabove indicute-d, one of the principal objects and advantages of the invention is to provide in conjunction with a cartridge tube formed with spaced break-off points, first and second sleeves which can be slidably mounted on the cartridge tube body in end--to-cnd relationship, and with the adjoining ends of. the sleeve disposed coincident with any one of the break-off grooves to provide leverage fulcrum points proximate the exact point where the break-ofi is to occur. Thus, for example, Fig/ 3 discloses sleeves B and C The inside diameter of sleeves B and C v mounted on the cartridge tube A in end-to-end relationship and with the adjoining ends of the tube disposed coincident with one of the break-01f grooves 16 where the break-off has commenced to occur. In this regard, the cartridge tube can be cleanly and precisely broken at any one of the break-off grooves in the manner indicated in Fig. 3 by manually grasping the two sleeves B and C with ones hands and exerting a breaking force, much in the same manner as one would break a small stick or similar object by manual pressure.

in the preferred embodiment of the assembly, tube B is made substantially shorter in length than tube C and the combined lengths of the tubes should preferably be slightly shorter than the distance between cars 14 and the open upper end of the tube. In this regard, although the relative lengths of the sleeves B and C may be varied somewhat, it is desirable that the length of the shorter tube B not exceed the distance between the enlarged ears 14 and the innermost annular break-off groove 16. The reason for this is that when it is required to break off the cartridge tube at innermost break-off groove 16, for example, it is possible to slidably mount sleeve B on cartridge tube A between ears 14 and groove 16 and in such manner that the outer end of sleeve B can M be moved coincident with said groove 16 to establish the desired leverage fulcrum point.

In utilizing the present cartridge assembly as a refill in a commercial pen structure, the first step involved, of course, is to break off (if necessary) the cartridge tube A to the appropriate length that will fit the particular pen in question. The proper length and point of breakoff can be readily determined by removing the already existing cartridge from the pen, and using it as a gauge to proper length of the refill. It has been noted heretofore that there exists eleven variations in length of cartridge tubes among the 133 commercial pens on the market today of which I am aware, and that the breakoff grooves 16 shown in the drawings can be spaced and located relative to one another so as to provide a simple and efiicient means for selectively making the overall length of the tube properly fit any of these aforementioned commercial pen makes.

After the cartridge tube A has been broken to length to fit a given pen, it can be inserted within the pen casing as a refill replacement. Because many of the commercial brands of pens differ in both construction and mode of operation from one another, it is necessary to provide flexibility in the various ways in which the component elements comprising the present invention can be assembled within a pen casing to operate properly with all of the various makes. I

Figs. 4, 5 and 6 illustrate three different ways in which the components comprising the invention can be assem bled and utilized. More specifically, Fig. 4 is illustrative of one commercial type of pen construction which is shown as comprising upper and lower body or casing portions 21 and 22 adapted to be threadedly connected together as at 23. The upper body portion 22 is shown as housing a suitable push-button actuated cartridge tube extension and retraction means comprising, more specifically a piston 24 slidably mounted within body portion 22 and provided with a push-button extension 26. The

outer end of the push-button projects through an aperture formed in the upper end of the casing body. In operation, when the push-button 26 is pushed inwardly, corresponding reciprocal movement is imparted to piston 24 which, being abutted against the upper end of the cartridge tube, causes the ball-point end of the said cartridge to be extended outwardly to writing position as shown. In the arrangement of Fig. 4, spring D is mounted on the forward end of the cartridge tube body between the writing point end thereof and the crimp 13 whereby one end of the spring abuts against cars 14 and the opposite end thereof abuts against a spring seat 27 which is customarily provided in the typical or standard type of pen construction illustrated. Hence, inward movement of thepush-button 26 which causes the ball-point end of the cartridge tube to extend outwardly in writing position as aforesaid, is against the force of spring D.

In order to retain the ball-point end of the tube in extended position, the pen is provided with a suitable push-button lock or retainer mechanism. Fig. 4 shows this mechanism as comprising a spring biased catch member 28 which can be depressed out of locking engagement with a retaining slot formed in the casing body 22 simply by pressing inwardly against the pocket clip member 29 located in overlying relationship with respect to plunger catch 28 when the parts are in locked position. Upon compression of the catch and its consequent release from its retaining slot, the force of spring D acting against ears 14 will cause the ball-point end of the cartridge tube to retractwithin its casing and will cause the push-button 26 to move outwardly to its extended position. It is understood that the push-button extension and retraction mechanism shown in Fig. 4 and above briefly described is conventional and well-known in the art, and, accordingly, the same does not comprise a part of the present invention.

It is to be further noted with regard to the pen assembly illustrated in Fig. 4 that the pen casing is designed to accommodate what may be conveniently considered as a more or less standard Ms inch diameter cartridge tube. In view of the fact that this is also the preferred diameter of cartridge tube A comprising the present invention, there is no need to employ either of the sleeves B or C to enlarge the diameter of tube A as will be described with reference to the assembly shown in Fig. 5, for example. Hence, the only function of the sleeves B and C in providing an assembly of the type shown in Fig. 4 is to facilitate the breaking ofi of the cartridge tube to proper length in the manner already explained.

Fig. 5 is illustrative of a second type of pen construction commercially produced today. In this arrangement, the pen casing also comprises upper and lower body portions 31 and 32 threadedly joined together as at 33. There is also provided a suitable cartridge tube extension and retraction mechanism which is shown as comprising an integral hollow push-button member 34 slidably reciprocably mounted within the hollow interior of upper body portion 32 of the pen casing. Member 34 is normally spring biased to its outwardly extending position by spring 36 mounted within housing 37 and having a sulficiently large diameter to slidably accommodate the cartridge tube unit which extends substantially the full length of the pen casing and through the central bore formed in member 34. The push-button retainer mechanism is shown as comprising a rearwardly extending flat spring 38 adapted to engage an abutment ledge 39 formed in the casing when the push-button assembly is moved inwardly to cause the writing point of the cartridge tube to extend to writing position. The pocket clip 41 is mounted to the casing body portion 32 by means of a flat spring 42 whereby the pocket clip can function in effect as a rocker arm. The upper end of the clip is formed with an inwardly bent portion 43 overlying retaining spring 38. Accordingly, when the upper end of the pocket clip is pressed inwardly against flat spring 38, the push-button member is released to slide upwardly in the pen casing under force of spring 36. It is again understood that the cartridge tube extension and retraction member mechanism hereinabove briefly described is conventional and well-known in the art, and does not in and of itself comprise a part of the present invention.

It is important to note, however, that the type of pen construction shown in Fig. 5 is adapted to utilize a substantially larger diameter and longer cartridge tube than that utilized in the pen construction shown in Fig. 4, for example. Hence, in order to accommodate the present assembly to the pen construction shown in Fig. 5, the

sleeves B and C may be slidably mounted on the cartridge tube body between the upper open tube end and crimp 13 so as to effectively enlarge the diameter of the cartridge tube. It is observed that the upper or outer end of the tube C abuts against stop member 44 which, in the type of pen construction shown in Fig. 5, is provided as an inherent or conventional component thereof. Spring D may be utilized to normally spring bias the cartridge tube to retracted position within the casing and is assembled within said casing in substantially the identical manner as described above with reference to Fig. 4.

Fig. 6 illustrates still another variation in assembly of the components comprising the present invention. For purposes of brevity, it may be assumed that the pen construction shown fragmentarily in Fig. 6 is provided with some type of cartridge tube extension and retraction mechanism such as, for example, one of the general types hereinabove briefly described with reference to Figs. 4 and 5. However, because the push-button retaining mechanisms on certain makes of pens are not capable of securely locking the cartridge tube in extended writing position against the force of a relatively long and strong spring (such as I prefer to provide as component D of the present assembly), it is convenient, when utilizing a cartridge assembly of the present type as a refill for such pens, to re-use the relatively shorter and weaker spring (as indicated at 46) that is conventionally incorporated in the pens by the manufacturer as an original component thereof. In these circumstances, the shorter sleeve B may be mounted on the forward portion of the cartridge tube body as a spacer member between crimp 13 and the inner end of spring 46. In short, because the shorter spring 46 is not long enough to engage between spring seat 27 of the casing and the crimped ears 14 of the cartridge tube, sleeve B may be utilized in the manner shown in Fig. 6 with one end abutting against ears 14 and with the opposite end of the sleeve providing an abutment surface against which the inner end of spring 46 may bear.

From the foregoing description, it is seen that the present invention comprises a unique combination of elements which provides for flexibility and variation in the manner in which the components may be utilized and assembled-the end result being that it is possible to provide a single refill cartridge unit that may be efliciently and satisfactorily adapted for utilization with any one of the some 133 commercial ball-point pens on the market today of which I am aware.

Although the present invention has been described in some detail by way of illustration and example for purposes of clarity of understanding, it is understood that certain changes and modifications may be practiced within the spirit of the invention as limited only :by the scope of the claims appended hereto.

I claim:

1. A ball-point pen cartridge assembly for use with pens varying in length comprising: a cartridge casing comprising an integral elongate hollow tube provided at its first end with a ball point; a crimp formed in the body of said tube intermediate the ends thereof defining laterally projecting abutment ears; a plurality of spaced annular non-through-going break-off grooves formed in the tube between said crimp and the second end of said tube; first and second tubular sleeves each having a diameter only slightly larger than the outside diameter of said cartridge tube; said sleeves slidably positionable on said cartridge tube in end-to-end relation with adjacent ends of said sleeves positioned substantially coincident with any preselected break-elf groove thereby providing leverage fulcrum points proximate said groove to facilitate breaking of said cartridge tube precisely at the point of said groove.

2. A ball-point pen cartridge assembly according to claim 1 and wherein the length of at least one of said sleeves does not exceed the distance between the inner- 7 most break-oft groove and said crimped abutment ears on said tube.

3. The combination of claim 1 and wherein said first and second tubular sleeves are of different lengths and wherein the combined length of both sleeves does not exceed the distance between said abutment ears and the second end of said tube; the length of said shorter sleeve not exceeding the distance between said abutment ears and the innermost break-off groove.

4. The combination of claim 1 and wherein said first and second tubular sleeves are of difierent lengths; the length of the shorter sleeve being substantially less than the distance between said abutment ears and the first end of s'aidtube to permit said shorter sleeve to be slidably mounted on said cartridge tube between said abutment ears and the first end of said tube to provide a spacer between said abutment ears and the first end of said cartridge casing.

5. A ball-point pen cartridge assembly for use with pens varyng in length comprising: a cartridge casing comprising an integral elongate hollow tube provided at its first end with a ball-point; said tube defining an ink reservoir adjacent the first end in communication with said ball-point; the second end of said tube defining a vent opening communicating with said ink reservoir; a plurality of spaced annular non-through-going break-cit grooves formed in the tube between said ink reservoir and the second end of said tube; and leverage break-off means longitudinally positionable relative to said tube and selectively positionable coincident with any preselected breakofi groove to facilitate breaking of said cartridge tube at the point of said preselected groove.

References Cited in the file of this patent UNITED STATES PATENTS 1,066,333 Snyder July 1, 1913 2,692,580 Kahn et a1 Oct. 26, 1954 2,702,578 Hoffman Feb. 22, 1955 FOREIGN PATENTS 1,020,925 France Nov. 26, 1952 1,032,775 France Apr. 1, 1953 

